anastasis

lae_credit.c (9936B)

---

 /*
   This file is part of Anastasis
   Copyright (C) 2017--2021 Anastasis SARL
 
   Anastasis is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License
   as published by the Free Software Foundation; either version 3,
   or (at your option) any later version.
 
   Anastasis is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
 
   You should have received a copy of the GNU General Public
   License along with Anastasis; see the file COPYING.  If not,
   see <http://www.gnu.org/licenses/>
 */
 /**
  * @file libanastasiseufin/lae_credit.c
  * @brief Implementation of the /history requests of the
  *        Taler revenue API (as served by libeufin-bank)
  * @author Christian Grothoff
  * @author Marcello Stanisci
  */
 #include "platform.h"
 #include "lae_common.h"
 #include <microhttpd.h> /* just for HTTP status codes */
 
 
 /**
  * @brief A /history Handle
  */
 struct ANASTASIS_EUFIN_CreditHistoryHandle
 {
 
   /**
    * The url for this request.
    */
   char *request_url;
 
   /**
    * Handle for the request.
    */
   struct GNUNET_CURL_Job *job;
 
   /**
    * Function to call with the result.
    */
   ANASTASIS_EUFIN_CreditHistoryCallback hcb;
 
   /**
    * Closure for @a cb.
    */
   void *hcb_cls;
 };
 
 
 /**
  * Parse history given in JSON format and invoke the callback on each item.
  *
  * @param hh handle to the account history request
  * @param history JSON array with the history
  * @return #GNUNET_OK if history was valid and @a rhistory and @a balance
  *         were set,
  *         #GNUNET_SYSERR if there was a protocol violation in @a history
  */
 static enum GNUNET_GenericReturnValue
 parse_account_history (struct ANASTASIS_EUFIN_CreditHistoryHandle *hh,
                        const json_t *history)
 {
   json_t *history_array;
   const char *credit_account_uri;
 
   if (NULL == (history_array = json_object_get (history,
                                                 "incoming_transactions")))
   {
     GNUNET_break_op (0);
     return GNUNET_SYSERR;
   }
   if (! json_is_array (history_array))
   {
     GNUNET_break_op (0);
     return GNUNET_SYSERR;
   }
   /* The credited account is the account we asked about, so the revenue API
      states it once for the whole response instead of per transaction. */
   credit_account_uri = json_string_value (json_object_get (history,
                                                            "credit_account"));
   if (NULL == credit_account_uri)
   {
     GNUNET_break_op (0);
     return GNUNET_SYSERR;
   }
   for (size_t i = 0; i<json_array_size (history_array); i++)
   {
     struct ANASTASIS_EUFIN_CreditDetails td;
     uint64_t row_id;
     struct GNUNET_JSON_Specification hist_spec[] = {
       TALER_JSON_spec_amount_any ("amount",
                                   &td.amount),
       GNUNET_JSON_spec_timestamp ("date",
                                   &td.execution_date),
       GNUNET_JSON_spec_uint64 ("row_id",
                                &row_id),
       GNUNET_JSON_spec_string ("subject",
                                &td.wire_subject),
       GNUNET_JSON_spec_string ("debit_account",
                                &td.debit_account_uri),
       GNUNET_JSON_spec_end ()
     };
     json_t *transaction = json_array_get (history_array,
                                           i);
 
     td.credit_account_uri = credit_account_uri;
     if (GNUNET_OK !=
         GNUNET_JSON_parse (transaction,
                            hist_spec,
                            NULL, NULL))
     {
       GNUNET_break_op (0);
       return GNUNET_SYSERR;
     }
     if (GNUNET_OK !=
         hh->hcb (hh->hcb_cls,
                  MHD_HTTP_OK,
                  TALER_EC_NONE,
                  row_id,
                  &td))
     {
       hh->hcb = NULL;
       GNUNET_JSON_parse_free (hist_spec);
       return GNUNET_OK;
     }
     GNUNET_JSON_parse_free (hist_spec);
   }
   return GNUNET_OK;
 }
 
 
 /**
  * Function called when we're done processing the
  * HTTP /history request.
  *
  * @param cls the `struct ANASTASIS_EUFIN_CreditHistoryHandle`
  * @param response_code HTTP response code, 0 on error
  * @param response parsed JSON result, NULL on error
  */
 static void
 handle_credit_history_finished (void *cls,
                                 long response_code,
                                 const void *response)
 {
   struct ANASTASIS_EUFIN_CreditHistoryHandle *hh = cls;
   const json_t *j = response;
   enum TALER_ErrorCode ec;
 
   hh->job = NULL;
   switch (response_code)
   {
   case 0:
     ec = TALER_EC_GENERIC_INVALID_RESPONSE;
     break;
   case MHD_HTTP_OK:
     if (GNUNET_OK !=
         parse_account_history (hh,
                                j))
     {
       GNUNET_break_op (0);
       response_code = 0;
       ec = TALER_EC_GENERIC_INVALID_RESPONSE;
       break;
     }
     response_code = MHD_HTTP_NO_CONTENT; /* signal end of list */
     ec = TALER_EC_NONE;
     break;
   case MHD_HTTP_NO_CONTENT:
     ec = TALER_EC_NONE;
     break;
   case MHD_HTTP_BAD_REQUEST:
     /* This should never happen, either us or the bank is buggy
        (or API version conflict); just pass JSON reply to the application */
     GNUNET_break_op (0);
     ec = TALER_JSON_get_error_code (j);
     break;
   case MHD_HTTP_UNAUTHORIZED:
     /* Nothing really to verify, bank says the HTTP Authentication
        failed. May happen if HTTP authentication is used and the
        user supplied a wrong username/password combination. */
     ec = TALER_JSON_get_error_code (j);
     break;
   case MHD_HTTP_NOT_FOUND:
     /* Nothing really to verify: the bank is either unaware
        of the endpoint (not a bank), or of the account.
        We should pass the JSON (?) reply to the application */
     ec = TALER_JSON_get_error_code (j);
     break;
   case MHD_HTTP_INTERNAL_SERVER_ERROR:
     /* Server had an internal issue; we should retry, but this API
        leaves this to the application */
     ec = TALER_JSON_get_error_code (j);
     break;
   default:
     /* unexpected response code */
     GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                 "Unexpected response code %u\n",
                 (unsigned int) response_code);
     ec = TALER_JSON_get_error_code (j);
     break;
   }
   if (NULL != hh->hcb)
     hh->hcb (hh->hcb_cls,
              response_code,
              ec,
              0LLU,
              NULL);
   ANASTASIS_EUFIN_credit_history_cancel (hh);
 }
 
 
 struct ANASTASIS_EUFIN_CreditHistoryHandle *
 ANASTASIS_EUFIN_credit_history (
   struct GNUNET_CURL_Context *ctx,
   const struct ANASTASIS_EUFIN_AuthenticationData *auth,
   uint64_t start_row,
   int64_t num_results,
   struct GNUNET_TIME_Relative timeout,
   ANASTASIS_EUFIN_CreditHistoryCallback hres_cb,
   void *hres_cb_cls)
 {
   char url[128];
   struct ANASTASIS_EUFIN_CreditHistoryHandle *hh;
   CURL *eh;
   unsigned long long tms;
 
   if (0 == num_results)
   {
     GNUNET_break (0);
     return NULL;
   }
 
   tms = (unsigned long long) (timeout.rel_value_us
                               / GNUNET_TIME_UNIT_MILLISECONDS.rel_value_us);
   if ( ( (UINT64_MAX == start_row) &&
          (0 > num_results) ) ||
        ( (0 == start_row) &&
          (0 < num_results) ) )
   {
     if ( (0 < num_results) &&
          (! GNUNET_TIME_relative_is_zero (timeout)) )
       GNUNET_snprintf (url,
                        sizeof (url),
                        "history?limit=%lld&timeout_ms=%llu",
                        (long long) num_results,
                        tms);
     else
       GNUNET_snprintf (url,
                        sizeof (url),
                        "history?limit=%lld",
                        (long long) num_results);
   }
   else
   {
     if ( (0 < num_results) &&
          (! GNUNET_TIME_relative_is_zero (timeout)) )
       GNUNET_snprintf (url,
                        sizeof (url),
                        "history?limit=%lld&offset=%llu&timeout_ms=%llu",
                        (long long) num_results,
                        (unsigned long long) start_row,
                        tms);
     else
       GNUNET_snprintf (url,
                        sizeof (url),
                        "history?limit=%lld&offset=%llu",
                        (long long) num_results,
                        (unsigned long long) start_row);
   }
   hh = GNUNET_new (struct ANASTASIS_EUFIN_CreditHistoryHandle);
   hh->hcb = hres_cb;
   hh->hcb_cls = hres_cb_cls;
   hh->request_url = TALER_url_join (auth->wire_gateway_url,
                                     url,
                                     NULL);
   if (NULL == hh->request_url)
   {
     GNUNET_free (hh);
     GNUNET_break (0);
     return NULL;
   }
   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
               "Requesting credit history at `%s'\n",
               hh->request_url);
   eh = curl_easy_init ();
   if ( (NULL == eh) ||
        (GNUNET_OK !=
         ANASTASIS_EUFIN_setup_auth_ (eh,
                                      auth)) ||
        (CURLE_OK !=
         curl_easy_setopt (eh,
                           CURLOPT_URL,
                           hh->request_url)) )
   {
     GNUNET_break (0);
     ANASTASIS_EUFIN_credit_history_cancel (hh);
     if (NULL != eh)
       curl_easy_cleanup (eh);
     return NULL;
   }
   if (0 != tms)
   {
     GNUNET_break (CURLE_OK ==
                   curl_easy_setopt (eh,
                                     CURLOPT_TIMEOUT_MS,
                                     (long) tms));
   }
   hh->job = GNUNET_CURL_job_add2 (ctx,
                                   eh,
                                   NULL,
                                   &handle_credit_history_finished,
                                   hh);
   return hh;
 }
 
 
 void
 ANASTASIS_EUFIN_credit_history_cancel (
   struct ANASTASIS_EUFIN_CreditHistoryHandle *hh)
 {
   if (NULL != hh->job)
   {
     GNUNET_CURL_job_cancel (hh->job);
     hh->job = NULL;
   }
   GNUNET_free (hh->request_url);
   GNUNET_free (hh);
 }
 
 
 /* end of lae_credit.c */